NASA officials have chosen Air Force Plant 42 over Kennedy Space Center in Florida as the spot for inspections and modifications for space shuttle Endeavour, officials said Tuesday.

Endeavour, the newest of the nation’s shuttles, will be flown to Air Force Plant 42 atop a modified 747 airliner Aug. 6, about six weeks after the completion of modifications to the shuttle Discovery, Rockwell spokesman Alan Buis said.

“These major modifications should be performed by a dedicated team as opposed to the share-resources approach used at Kennedy Space Center,” NASA space shuttle program manager Tommy W. Holloway said in a letter released by Rockwell.

Endeavour’s modification should employ about the same 300 workers now busy on Discovery, who were told earlier this month that they will have another shuttle to modify, Buis said.

NASA officials have not decided whether Atlantis, the next spacecraft due for inspections and modifications, will be sent to Palmdale or to Kennedy.

In the March 8 memo in which he announced his decision to send Endeavour to Palmdale, Holloway said he will review in August the issue of where Atlantis will be sent. Endeavour is scheduled to be in Palmdale until early April 1997.

Making its first visit to Palmdale since its rollout in April 1991 as the replacement for the ill-fated Challenger, Endeavour will be disassembled in large part and checked for wear and fatigue, as well as modified for international space station missions and fitted with other improvements.

More than 100 modifications will be made, Buis said. Those include adding a docking device to fit the international space station and installing lighter-weight thermal protection against re-entry heat, he said.

Discovery’s modifications include new equipment for docking with the Russian space station Mir and the international space station.

For four years, NASA officials have toyed with the idea of keeping shuttles in Florida – saving the cost of flying them across the country – for modifications and inspections, to the alarm of Rockwell and Antelope Valley officials.

In 1992, Atlantis had been earmarked to be modified in Florida, but company and government officials lobbied successfully to keep the work at Plant 42, where all the spacecraft were built.

In his letter explaining his decision about Endeavour, Holloway said one of his reasons was the likelihood that doing the extensive modification work in Florida would interfere with getting other shuttles ready for launch during 1997.

Doing the work in Florida would tie up one of the giant orbiter processing facilities and require hiring and training workers, the letter said.